please show step by step calculation

PART- II. (This part has no link to PART-I) Chimney Commercial Pipes Fabricating Company (CCPFC) produces many different kinds of plastic pipes for commercial uses. Plastic pipe is used for plumbing in almost all new homes. If the pipes are too narrow or too wide, they will not connect appropriately with other parts of the plumbing system. The operations manager, Steve, wants to make sure that the production process is producing products (3-inch diameter pipe) within acceptable tolerance limits where diameter of pipe should be measured within 3 + 0.08 inches. To test this, the operator takes several sample measurements and determines the mean of the process to be 2.9920 inches with a standard deviation of 0.0341 inches, (1I-a) Calculate the process capability index and interpret it. (II-b) What percent of the current production is expected to be within the given tolerance limits